Matrix libs in as3?

[realMakc]

We all know that each and every flash 3D engine comes with 4x4 matrix math code (and sometimes 3x3 operations included), but recently I ran into a problem solving equation involving 4x3 (and, obviously 3x4) matrices at runtime. Having no suitable code at hand, I resorted to mathcad symbolic solution in terms of numbers that make up these matrices; needless to say, implementing these expressions is not fun. So. Does anyone know solid matrix math library for as3 that can operate with matrices of any dimensions?

[newblack]

You can try this. I don't seem to remember ever testing it, so don't assume everything works! It's Flash 10

http://lab.generalrelativity.org/file/MatrixND.as

EDIT: Meh, looked at it, looks like it only has square matrix solvers...

[realMakc]

Interestingly enough, top google hits for non-square matrix inverse all say that there is no inverse for non-square matrices, and one should resort to LS/QR/SVD. If that's really so, I am puzzled how mathcad was able to find exact solution of my problem. Maybe I had a typo somewhere, but we'll see once I will implement it.

[realMakc]

Yep, that was a typo, I missed few variables, hence no solution for me

[newblack]

that sucks... what are you trying to solve?

[realMakc]

if you have to ask I was trying to solve for 3d coords from 2d coords of 3 points for sort of augmented reality experiment (but without flartoolkit), and I missed how their z-s remained in what I thought was solution, so I had to estimate z-s in some other way (I had some limited success here btw). I've found some article on homography that said it takes at least 4 points, which brings us back to 4x4 matrices, I guess, and more than 4 points naturally go with LS.

[realMakc]

I don't seem to remember ever testing it, so don't assume everything works!

I finally got back to this, and tested, and there's actually a bug or restriction of some sort in the code. Check it out here (scroll down to line 107), let me know what you think...

[realMakc]

duhh, found the answer here:

If the matrix A is positive definite symmetric or if the matrix is diagonally dominant, then pivoting is not necessary; otherwise the version using pivoting should be used.

looks like I need to edit your code a bit more

[KigD]

Here's an Actionscript 3 Matrix Library:
http://k2xl.com/wordpress/2010/12/27...atrix-library/

Direct link to library: http://code.google.com/as3matrix/

[realMakc]

You mean http://code.google.com/p/as3matrix/ checking...